Patents by Inventor Roland Wilhelmus Pieter Jonkers

Roland Wilhelmus Pieter Jonkers has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8573600
    Abstract: The invention relates to an improved O-ring seal for use as a high vacuum seal. A limitation of standard O-ring seals is the permeation of water through the O-ring. Especially for instruments in which parts are kept at a cryogenic temperature, such as a cryogenic electron microscope, the presence of water in the vacuum is a problem, as this results in ice growth on the cryogenic parts. As a solution often a double O-ring seal is used, or a metal seal. Both of these solutions have severe draw-backs. The invention proposes to place the O-ring in a channel in which dry gas, such as dry nitrogen, is blown. In this way no water can permeate through the O-ring, resulting in a reduced base pressure and highly reduced ice growth.
    Type: Grant
    Filed: September 7, 2010
    Date of Patent: November 5, 2013
    Assignee: FEI Company
    Inventors: Stephanus Hubertus Leonardus van den Boom, Roland Wilhelmus Pieter Jonkers, Henricus Fransiscus Maria van den Boom, Rients Jan de Groot, Pieter Hendrik Trudo Johannes Uland
  • Publication number: 20110057393
    Abstract: The invention relates to an improved O-ring seal for use as a high vacuum seal. A limitation of standard O-rig seals is the permeation of water through the O-ring. Especially for instruments in which parts are kept at a cryogenic temperature, such as a cryogenic electron microscope, the presence of water in the vacuum is a problem, as this results in ice growth on the cryogenic parts. As a solution often a double O-ring seal is used, or a metal seal. Both of these solutions have severe draw-backs. The invention proposes to place the O-ring in a channel in which dry gas, such as dry nitrogen, is blown. In this way no water can permeate through the O-ring, resulting in a reduced base pressure and highly reduced ice growth.
    Type: Application
    Filed: September 7, 2010
    Publication date: March 10, 2011
    Applicant: FEI Company
    Inventors: Stephanus Hubertus Leonardus van den Boom, Roland Wilhelmus Pieter Jonkers, Henricus Fransiscus Maria van den Boom, Pieter Hendrik Trudo Johannes Uland, Rients Jan de Groot